A. Field of the Invention:
The METERING CASTING LADLE was originally designed for, and has been utilized to good advantage in the field of bullet casting. Lead alloy bullets produced by casting are extensively used as projectiles for handgun and rifle shooting. Although not suitable for every shooting need, cast lead alloy bullets are economical, perform well in some applications and can be easily crafted by the hobbyist at home.
Standard bullet casting equipment consists of a bullet mould and a lead melting pot (usually gas or electric). The molten lead alloy is dispensed into the bullet mould by the melting pot's pouring spout or by a separate ladle to produce a solid, monometallic casting.
Selecting a lead casting alloy with mechanical properties suitable to the intended shooting task sometimes leads to a dilemma. If bullet expansion upon impact with the target is desirable, as it would be for many hunting situations, a softer lead alloy would be preferred. But soft lead alloy bullets generally exhibit poor functional performance: lead fouling in the gun barrel and erratic shooting accuracy. The stresses produced in attaining a velocity high enough to cause a lead alloy projectile of a given hardness to effectively expand upon impact will generally exceed the functional strength level of that lead alloy. Increasing bullet hardness allows higher effective shooting velocity, but further inhibits terminal expansion. A softer bullet would expand easier, but cannot be efficiently driven fast enough to ensure its own expansion. Shooting unjacketed (bare lead) cast bullets has always been a compromising situation when an expanding projectile would be advantageous, until now.
The METERING CASTING LADLE is designed to accurately dispense a calibrated volume of clean molten metal from its melter to a mould. A quantity of soft lead alloy can be injected into the nose portion of a bullet mould cavity with the METERING CASTING LADLE (not completely filling the cavity), and the remainder of the cavity filled with a hard lead alloy by conventional means. The two lead alloys thoroughly fuse at their junction to produce a one-piece cast bullet with a soft, expandable nose, and a hard, strong body to withstand the stresses of high velocity shooting.
B. Description of Prior Art:
Producing dual-alloy castings has always been hindered by the lack of a practical means to accurately meter the desired quantity of the first metal alloy to go into the mould. When using a common casting ladle, there is no way to precisely control the volume of metal being poured. Furthermore, the presence of oxides and other impurities on the surface of a molten metal, along with the elevated temperatures involved, render common methods of dispensing accurate volumes of cold fluids unsatisfactory.
Strong-bodied expanding bullets have been made by casting two separate pieces (a soft nose section and a hard body section), then joining them by mechanical or adhesive means. In most cases where an expanding projectile is deemed necessary, the practical shooter would choose a copper or gilding metal jacketed soft-nose or hollow-point bullet. The soft-nose, dual-alloy cast bullet produced with the METERING CASTING LADLE is an economical and effective alternative to costly jacketed bullets for many shooting activities.